基于地下结构整体损伤表征的复合地震动参数构造及其性能验证  

Construction and verification of composite intensity measure representing the overall damage of underground structures

作　　者：陈之毅[1] 余伟[1] 刘志谦 Chen Zhiyi;Yu WeiLiu;Zhiqian Tongji(University,Shanghai 200082,China)

机构地区：[1]同济大学,上海200082

出　　处：《土木工程学报》2024年第4期23-33,共11页China Civil Engineering Journal

摘　　要：在地下结构抗震设计中,不同的输入地震动引起的地下结构响应有显著差异,因此,合理通过地震动参数选择输入地震动是正确开展地下结构抗震设计的重要前提。针对单一地震动参数难以表征地下结构地震动潜在破坏势问题,文章构造了能更好表征地下结构损伤破坏的复合地震动参数。具体开展了以下工作:提出基于变形与滞回耗能的地下结构整体损伤指标作为结构需求参数,以定量化评估地下结构的整体破坏状态。选取64条真实地震动记录作为输入地震动,开展四层三跨地铁车站地震弹塑性动力时程分析。基于分析结果提供的数据样本,采用偏最小二乘法从统计角度构造复合地震动参数。最后,选用100条真实地震动记录开展两层三跨地铁车站弹塑性动力时程分析,对文章所构造的复合地震动参数进行验证。对比分析复合地震动参数、12个常用地震动参数与地下结构整体损伤指数的回归统计特征。结果表明:复合地震动参数与结构需求数之间具有更好拟合优度值,其Pearson相关性、有效性也优于单一地震动参数。In the seismic design of underground structures,the responses of underground structures caused by different input ground motions are significantly different.Therefore,reasonable selection of input ground motions through ground motion intensity measures(IM)is an important prerequisite for correct seismic design of underground structures.In order to solve the problem that it is difficult to characterize the most damage potential of underground structures with a single IM,a composite IM,which can better characterize the failure of underground structures,is constructed.In this work,the following studies are specifically carried out:the overall damage index of underground structure based on deformation and hysteretic energy is proposed as an engineering demand parameter(EDP)to quantitatively evaluate the overall damage state of underground structure.64 real ground motion records are selected as input ground motions to carry out seismic elastoplastic dynamic time-history analysis of four-storey and three-span subway stations.Based on the data sample from the results of time history analysis,the composite IM is constructed from a statistical point of view using the partial least squares method.Finally,100 real ground motion records are selected to carry out elastoplastic dynamic time-history analysis of two-storey three-span subway stations to verify the constructed composite IM.The regression statistical characteristics of the composite IM,12 single IMs and the EDP of underground structure are compared and analyzed.The results show that the goodness of fit value between composite IM and EDP of underground structure shall be better than that of single IMs,and its Pearson correlation and effectiveness shall also be better than single IMs.

关 键 词：地下结构 复合地震动参数 整体损伤指数 弹塑性动力时程分析 偏最小二乘 回归分析 

分 类 号：TU93[建筑科学—结构工程]